Control device and radio control method

ABSTRACT

A controller equipment includes a measuring unit for measuring channel qualities of a control channel and a user channel separated from a received signal, an updating unit for updating target circuit qualities for the control channel and the user channels, based on results of measurement of the channel qualities by the measuring units, a communicating unit for communicating, in a predetermined period, the updated target circuit qualities for the control channel and the user channel, and a target circuit quality determining unit for determining a target circuit quality for the received signal, based on the target circuit qualities for the control channel and the user channel communicated from the communicating unit, so that all of the control channel and user channels satisfy a required channel quality. When the channel quality of the control channel satisfies a predetermined condition, the communicating unit communicates at least the target circuit quality for the control channel, and the target circuit quality determining unit determines a target circuit quality for the received signal, based on the communicated target circuit quality for the control channel.

TECHNICAL FIELD

The present invention relates to a controller equipment and a radiocommunication method for implementing a transmit power control method ina radio communication system using a CDMA system or the like.

BACKGROUND ART

Transmit power control methods in radio communication systems using aCDMA system or the like have been known in which transmit power at atransmitter is controlled so as to make received power at a receiverconstant even when fluctuations in the propagation path occur.

As a first transmit power control method, a closed loop transmit powercontrol method is known in which a receiver compares a measured desiredwave to interference wave power ratio (SIR) to a desired SIR, and setstransmit power control bits based on a result of the comparison.

As a second transmit power control method, an outer loop transmit powercontrol method is known in which a receiver compares a measured receiveerror rate of a received signal to a preset target receive error rate,corrects a target SIR based on a result of the comparison, and setstransmit power control bits based on the corrected target SIR.

As a third transmit power control method, a closed loop transmit powercontrol method is known in which a receiver selects a data piece whichrequires the highest data quality from among the data pieces included ina received signal, and controls target circuit quality (target SIR) sothat the data quality of the selected data piece is satisfied. By usingthis closed loop transmit power control method, even when a plurality ofdata pieces requiring different data qualities are multiplexed on thesame channel, transmit power control can be properly performed.

With reference to FIG. 1, a radio communication system for implementingthe above-described third transmit power control method will bedescribed. For a radio control station shown in FIG. 1, a radio controlstation 3 is provided with main functions of outer loop transmit powercontrol, and a base station 2 is provided with main functions of closedloop transmit power control.

As shown in FIG. 1, the base station 2 is configured with an amplifierunit 21, a demodulator unit 25, a modulator unit 22, a frame generatingunit 23, a pattern determining unit 24, and a SIR measuring unit 26.

The amplifier unit 21 is configured to amplify a signal received from amobile station 1 for output. The amplifier unit 21 is also configured toamplify a spread signal outputted from the modulator unit 22 to acertain output for transmission to the mobile station 1.

The modulator unit 22 is configured to perform data modulationprocessing and spread modulation processing on a transmission frameoutputted from the frame generating unit 23 for output to the amplifierunit 21.

The frame generating unit 23 is configured to add transmit power controlbits determined by the pattern determining unit 24 to data bits to betransmitted, thereby forming a transmission frame.

The pattern determining unit 24 is configured to determine a transmitpower control bit pattern, based on a SIR measured by the SIR measuringunit 26 and a stored target SIR. Here, a target SIR stored isperiodically communicated from the radio control station 3.

The demodulator unit 25 is configured to perform despread demodulationprocessing and data demodulation processing on a signal outputted fromthe amplifier unit 21 for output to the SIR measuring unit 26 and theradio control station 3. The SIR measuring unit 26 is configured tomeasure a SIR based on a signal outputted from the demodulator unit 25.

The radio control station 3 is configured with a transport channel(TrCH) separating unit 31, channel (CH) quality measuring units 321 to32 n, transport channel target SIR updating units 331 to 33 n, and atarget SIR determining unit 34.

The transport channel separating unit 31 is configured to separate aplurality of transport channels from a signal outputted from thedemodulator unit 25 of the base station 2.

The channel quality measuring units 321 to 32 n are configured tomeasure the channel qualities of the separated transport channels.

The transport channel target SIR updating units 331 to 33 n areconfigured to compare channel qualities measured by the channel qualitymeasuring units 321 to 32 n with preset target channel qualities forrespective transport channels, and to update target SIRs for therespective transport channels.

Also, the transport channel target SIR updating units 331 to 33 n areconfigured to update the target SIRs for the respective transportchannels, based on the target SIR communicated from the target SIRdetermining unit 34.

The target SIR determining unit 34 is configured to compare the updatedtarget SIRs for the respective transport channels, and to determine atarget SIR which satisfies the channel qualities of all transportchannels for communication to the base station 2.

At the same time, the target SIR determining unit 34 is configured tocommunicate the determined target SIR to the respective transportchannel target SIR updating units 331 to 33 n.

In some cases, in the conventional radio communication system shown inFIG. 1, the radio control station 3 communicates the determined targetSIR to the base station 2 in predetermined periods, not in real time,for the purposes of reducing the load of the radio control station 3 andreducing the circuit capacity between the radio control station 3 andthe base station 2.

The conventional radio communication system, however, has the problemthat when user transport channels and a control transport channel aremultiplexed into a signal, even if a receive error occurs in the controltransport channel, for example, a target SIR is not improved until apredetermined period comes, and there is the possibility that a longpredetermined period can prevent flow of control data and establishmentof communication.

The present invention has been made in view of the above problems, andhas an object of providing a controller equipment and a radiocommunication method with which, in the case where a radio controlstation communicates a target SIR in outer loop transmit power controlto a base station in predetermined periods, not in real time, anadequate circuit quality can be maintained with a minimum increase inthe load of the radio control station and a minimum increase in thecircuit capacity between the radio control station and the base station.

DISCLOSURE OF THE INVENTION

A first aspect of the present invention is summarized as a controllerequipment including: a measuring unit configured to measure channelqualities of a control channel and a user channel separated from areceived signal; an updating unit configured to update target circuitqualities for the control channel and the user channel, based on resultsof measurement of the channel qualities by the measuring units; acommunicating unit configured to communicate, in a predetermined period,the updated target circuit qualities for the control channel and theuser channel; and a target circuit quality determining unit configuredto determine a target circuit quality for the received signal, based onthe target circuit qualities for the control channel and the userchannel communicated from the communicating unit, so that all of thecontrol channel and the user channel satisfy required channel qualities.When the channel quality of the control channel satisfies apredetermined condition, the communicating unit is configured tocommunicate at least the target circuit quality for the control channelto the target circuit quality determining unit. The target circuitquality determining unit is configured to determine the target circuitquality for the received signal, based on the communicated targetcircuit quality for the control channel.

In the first aspect, the communicating unit can be configured to comparethe channel quality of the control channel with a predeterminedthreshold in a period shorter than the predetermined period, and tocommunicate the updated target circuit quality for the control channelto the target circuit quality determining unit based on a result of thecomparison.

In the first aspect, when the channel quality of the control channelsatisfies a predetermined condition, the communicating unit can beconfigured to communicate the target circuit qualities for the controlchannel and the user channel to the target circuit quality determiningunit; and the target circuit quality determining unit can be configuredto determine the target circuit quality for the received signal, basedon the communicated target circuit qualities for the control channel andthe user channel.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a functional block diagram showing the configuration a radiocommunication system according to a related art;

FIG. 2 is a functional block diagram showing the configuration of aradio communication system according to a first embodiment of thepresent invention;

FIG. 3 is a flowchart showing an operation in a radio control stationaccording to the first embodiment of the present invention;

FIG. 4 is a transition diagram illustrating an example of updatetransitions of a target SIR for respective transport channels in thefirst embodiment of the present invention;

FIG. 5 is a flowchart showing an operation in a base station accordingto the first embodiment of the present invention;

FIG. 6 is a functional block diagram showing the configuration of aradio control station according to a second embodiment of the presentinvention;

FIG. 7 is a flowchart showing an operation in the radio control stationaccording to the second embodiment of the present invention; and

FIG. 8 is a transition diagram illustrating an example of updatetransitions of a target SIR for respective transport channels in thesecond embodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION First Embodiment

Hereinafter, with reference to the drawings, a first embodiment of thepresent invention will be described in detail. FIG. 2 is a functionalblock diagram showing the configuration of a radio communication systemin this embodiment. As shown in FIG. 2, the radio communicating systemof this embodiment includes a mobile station 1, a base station 2, and aradio control station 3.

As shown in FIG. 2, the radio control station 3 is a controllerequipment provided with a transport channel (TrCH) separating unit 31, acontrol transport channel (TrCH) quality measuring unit 35, usertransport channel (TrCH) quality measuring units 351 to 35 n, a controltransport channel (TrCH) target SIR updating unit 36, user transportchannel (TrCH) SIR updating units 361 to 36 n, a target SIR determiningunit 34, a control transport channel quality monitoring unit 37, atarget SIR communication control unit 38, and a timer unit 38 a.

The transport channel separating unit 31 is configured to separate acontrol transport channel and a plurality of user transport channelsfrom a signal (received signal) outputted from a demodulator unit 25 ofthe base station 2.

Here, a control transport channel is a control channel for transmittingcontrol data, and a user transport channel is a user channel fortransmitting one kind of user data. Through a transport channel, onekind of data (control data or user data) is transmitted. Multipletransport channels are multiplexed into a signal for transmission.

The control transport channel quality measuring unit 35 is configured tomeasure the channel quality of a control transport channel separated bythe transport channel separating unit 31.

The user transport channel quality measuring units 351 to 35 n areconfigured to measure the channel qualities of user transport channelsseparated by the transport channel separating unit 31.

In this embodiment, as the “channel quality”, the number of CRC-NGs, thenumber of block errors, the number of bit errors or the like is used,for example. ACRC is a signal for reporting on whether or not a receivedquality in a transport channel meets a predetermined condition.

The control transport channel target SIR updating unit 36 is configuredto update a target SIR (target circuit quality) for a control channel,based on a result of measurement of the channel quality (e.g., thenumber of CRC-NGs) by the control transport channel quality measuringunit 35.

Specifically, the control transport channel target SIR updating unit 36is configured to compare a channel quality measured by the controltransport channel quality measuring unit 35 with a preset target channelquality for the control transport channel, and to update a target SIRfor the control transport channel.

Also, the control transport channel target SIR updating unit 36 isconfigured to update a target SIR for the control transport channel,based on a target SIR communicated from the target SIR determining unit34.

For example, when a channel quality measured by the control transportchannel quality measuring unit 35 satisfies a target channel quality forthe control transport channel, the control transport channel target SIRupdating unit 36 reduces a target SIR for the control transport channel.

On the other hand, when a channel quality measured by the controltransport channel quality measuring unit 35 does not satisfy a targetchannel quality for the control transport channel, the control transportchannel target SIR updating unit 36 increases a target SIR for thecontrol transport channel.

Also, the control transport channel target SIR updating unit 36communicates an updated target SIR for the control transport channel tothe target SIR determining unit 34, in accordance with an instructionfrom the target SIR communication control unit 38.

The user transport channel target SIR updating units 361 to 36 n areconfigured to update target SIRs (target circuit qualities) for the userchannels, based on results of measurement of channel qualities (e.g.,the number of CRC-NGs) by the user transport channel quality measuringunits 351 to 35 n.

Specifically, the user transport channel target SIR updating units 361to 36 n are configured to compare channel qualities measured by the usertransport channel quality measuring units 351 to 35 n with targetchannel qualities preset for the user transport channels, and to updatetarget SIRs for the respective user transport channels.

Also, the user transport channel target SIR updating units 361 to 36 nare configured to update target SIRs for the user transport channel,based on a target SIR communicated by the target SIR determining unit34.

For example, when channel qualities measured by the user transportchannel quality measuring units 351 to 35 n satisfy target channelqualities for the respective user transport channels, the user transportchannel target SIR updating units 361 to 36 n reduce target SIRs for therespective user transport channel.

On the other hand, when channel qualities measured by the user transportchannel quality measuring units 351 to 35 n do not satisfy targetchannel qualities for the respective user transport channels, the usertransport channel target SIR updating units 361 to 36 n increase targetSIRs for the respective user transport channels.

Also, the user transport channel target SIR updating units 361 to 36 nare configured to communicate updated target circuit qualities for theuser transport channels to the target SIR determining unit 34, inaccordance with an instruction from the target SIR communication controlunit 38.

In this embodiment, description will be made on an example of using“SIR” as “circuit quality”, but the present invention is not limitedthereto, and is also applicable to the case of using “CIR (carrier waveto interference power ratio)”, “SNR (desired wave to noise powerratio)”, or “CNR (carrier wave to noise power ratio)”, for example.

The target SIR determining unit 34 is configured to determine a targetSIR for a received signal, based on a target SIR for the controltransport channel communicated from the control transport channel targetSIR updating unit 36, and target SIRs for the user transport channelscommunicated from the user transport channel target SIR updating units361 to 36 n, so that all of the control transport channel and the usertransport channels satisfy required channel qualities (target channelqualities).

The target SIR determining unit 34 is configured to communicate adetermined target SIR for the received signal to the base station 2 inpredetermined timing. Also, the target SIR determining unit 34 isconfigured to communicate a determined target SIR for the receivedsignal to the control transport channel target SIR updating unit 36 andthe user transport channel target SIR updating units 361 to 36 n.

When the target SIR determining unit 34 selects a target SIR having thelargest value (value of the highest quality) from among target SIRs forthe control transport channel and the user transport channels, all ofthe control transport channel and the user transport channels cansatisfy their target channel qualities.

The target SIR determining unit 34 may alternatively be configured toselect a target SIR having the latest value or the like from amongtarget SIRs for the control transport channel and the user transportchannels.

The control transport channel quality monitoring unit 37 is configuredto monitor measurement of the control transport channel qualitymeasuring unit 35.

Specifically, when the channel quality of a control transport channelmeasured by the control transport channel quality measuring unit 35becomes unable to satisfy a target channel quality for the controltransport channel, the control transport channel quality monitoring unit37 is configured to communicate that fact to the target SIRcommunication control unit 38.

The target SIR communication control unit 38 is configured to instruct,in a predetermined period (time measured by a target SIR determinationtimer), the transport channel target SIR updating units 36 and 361 to 36n to communicate current target SIRs for the respective transportchannel to the target SIR determining unit 34.

Also, when receiving a communication from the control transport channelquality monitoring unit 37, the target SIR communication control unit38, even not in the predetermined period, immediately instructs thetransport channel target SIR updating units 36 and 361 to 36 n tocommunicate current target SIRs for the respective transport channel tothe target SIR determining unit 34.

That is, when the channel quality of a control channel meets apredetermined condition, the control transport channel target SIRupdating unit 36 and the user transport channel target SIR updatingunits 361 to 36 n communicate an updated target circuit qualities forthe control channel and the user channel to the target SIR determiningunit 34 in a period shorter than the predetermined period, according toan instruction from the control transport channel quality monitoringunit 37 and the target SIR communication control unit 38.

The timer unit 38 a includes the target SIR determination timer, and isconfigured to communicate the fact that the predetermined period hascome to the target SIR communication control unit 38, when the targetSIR determination timer expires.

The base station 2 is an equipment for performing transmission andreception of a signal with the mobile station 1 through a radiocommunication circuit. Specifically, as shown in FIG. 2, the basestation 2 is provided with an amplifier unit 21, a modulator unit 22, aframe generating unit 23, a pattern determining unit 24, the demodulatorunit 25, and a SIR measuring unit 26.

The amplifier unit 21 is configured to amplify a signal received fromthe mobile station 1 for output. The amplifier unit 21 is alsoconfigured to amplify a spread signal outputted from the modulator unit22 to a certain output for transmission to the mobile station 1.

The modulator unit 22 is configured to perform data modulationprocessing and spread modulation processing on a transmission frameoutputted from the frame generating unit 23 for output to the amplifierunit 21.

The frame generating unit 23 is configured to add transmit power controlbits determined by the pattern determining unit 24 to data bits to betransmitted, thereby forming a transmission frame.

The pattern determining unit 24 is configured to determine a transmitpower control bit pattern, based on a SIR measured by the SIR measuringunit 26 and a stored target SIR. Here, the stored target SIR iscommunicated from the radio control station 3.

The demodulator unit 25 is configured to perform despread demodulationprocessing and data demodulation processing on a signal outputted fromthe amplifier unit 21 for output to the SIR measuring unit 26 and theradio control station 3. The SIR measuring unit 26 is configured tomeasure a SIR based on a signal outputted from the demodulator unit 25.

The base station 2 may be provided with the functions of the radiocontrol station 3 in this embodiment.

Hereinafter, with reference to FIG. 3, an operation in the radio controlstation according to this embodiment will be described.

As shown in FIG. 3, in step S101, the transport channel target SIRupdating units 36 and 361 to 36 n set initial target SIR values. Here,the initial target SIR values to be set are predetermined for thetransport channels by parameters.

In step S102, the timer unit 38 a starts the target SIR determinationtimer for monitoring the predetermined period.

In step S103, the transport channel separating unit 31 separates acontrol transport channel and respective user transport channels from asignal received from the base station 2. The control transport channelquality measuring unit 35 measures the channel quality of the controltransport channel. The user transport channel quality measuring units351 to 35 n measure the channel qualities of the respective usertransport channels.

In step S104, the control transport channel target SIR updating unit 36compares the measured channel quality of the control transport channelwith a set target channel quality for the control transport channel, andupdates the target SIR for the control transport channel.

The user transport channel target SIR updating units 361 to 36 n comparethe measured channel qualities of the respective user transport channelswith set target channel qualities for the respective user transportchannels, and update the target SIRs for the respective user transportchannels.

In step S105, the control transport channel quality monitoring unit 37determines whether the measured channel quality of the control transportchannel satisfies the target channel quality (required channel quality)or not.

When the determination is yes (“Y” in step S105), the operation proceedsto step S106. When the determination is no (“N” in step S105), theoperation proceeds to step S107.

In step S106, the target SIR communication control unit 38 determineswhether the time measured by the target SIR determination timer withinthe timer unit 38 a has expired or not, that is, whether thepredetermined period has come or not.

When the determination is yes (“Y” in step S106), the operation proceedsto step S107. When the determination is no (“N” in step S106), theoperation repeats the process of steps S103 to S106 by loop processing.

In step S107, the target SIR communication control unit 38 instructs thetransport channel target SIR updating units 36 and 361 to 36 n toimmediately communicate current target SIRs for the transport channel tothe target SIR determining unit 34. The target SIR determining unit 34determines a target SIR for a received signal, based on the communicatedtarget SIRs for the respective transport channel, so that the channelqualities of all transport channels satisfy their required channelqualities.

In step S108, the target SIR determining unit 34 communicates thedetermined target SIR for the received signal to the base station 2, andalso communicates the received signal target SIR to the transportchannel target SIR updating units 36 and 361 to 36 n.

In step S109, the transport channel target SIR updating units 36 and 361to 36 n update the target SIRs for the respective transport channel,based on the communicated target SIR.

FIG. 4 illustrates an example of update transitions of target SIRs forthe respective transport channel in this embodiment. FIG. 4 shows thecase where one control transport channel and two user transport channelsare multiplexed into a received signal.

In the example of FIG. 4, the transport channel target SIR updatingunits 36 and 361 to 36 n reduce the target SIRs for the respectivetransport channels by 1 dB, when receiving a CRC-OK as a measuredchannel quality from the transport channel quality measuring units 35and 351 to 35 n.

On the other hand, when receiving a CRC-NG as a measured channel qualityfrom the transport channel quality measuring units 35 and 351 to 35 n,the transport channel target SIR updating units 36 and 361 to 36 nincrease the respective target SIRs for the respective transportchannels by 1 dB.

Alternatively, when receiving a CRC-NG as a measured channel qualityfrom the transport channel quality measuring units 35 and 351 to 35 n,the transport channel target SIR updating units 36 and 361 to 36 n mayset different increases/decreases steps or decreases steps for therespective transport channels.

In this case, the transport channel target SIR updating units 36 and 361to 36 n may be configured to set the decreases step, based on theincreases/decreases step and required channel qualities of therespective transport channels.

In (1), initial target SIRs for all transport channels are set at 10 dB.

In (2), when the time measured by the target SIR determination timerexpires, the target SIR determining unit 34 compares current target SIRsfor all transport channels, and determines a target SIR of the highestquality as a target SIR for a received signal.

Here, since one CRC-OK and one CRC-NG are reported on the controltransport channel, the target SIR for the control transport channelremains 10 dB.

Also, since three CRC-OKs are reported (no CRC-NG is reported) on a usertransport channel 1, the target SIR for the user transport channel 1 isreduced to 7 dB.

Also, since two CRC-OKs are reported (no CRC-NG is reported) on a usertransport channel 2, the target SIR for the user transport channel 2 isreduced to 8 dB.

Accordingly, the target SIR determining unit 34 determines 10 dB, whichis the target SIR for the control transport channel, as a target SIR forthe received signal, and in (3), communicates the target SIR for thereceived signal (=10 dB) to the base station 2.

In (4), the target SIR determining unit 34 also communicates the targetSIR for the received signal (=10 dB) to the respective transport channeltarget SIR updating units 36 and 361 to 36 n. The respective transportchannel target SIR updating units 36 and 361 to 36 n update the targetSIRs for the respective transport channel to the communicated target SIRfor the received signal (=10 dB).

In (5), suppose that the channel quality of the control transportchannel is below a target channel quality. Here, the target SIRdetermining unit 34 compares current target SIRs for all transportchannels, and determines a target SIR of the highest quality as a targetSIR for the received signal.

In the example of FIG. 4, since the target SIR for the control transportchannel (=13 dB) is the highest, the target SIR for the controltransport channel is determined as a target SIR for the received signal.In (6), the determined target SIR for the received signal (=13 dB) iscommunicated to the base station 2.

Also, in (7), the target SIRs for the other user transport channels arechanged to the target SIR for the received signal (13 dB) communicatedto the base station 2. In (7), although the time measured by the targetSIR determination timer has not expired yet, the target SIRdetermination timer is reset.

In (8), when the time measured by the target SIR determination timerexpires, as in (2), the target SIR determining unit 34 compares currenttarget SIRs for all transport channel, and determines a target SIR ofthe highest quality (the target SIR for the user transport channel 1=12dB) as a target SIR for the received signal.

In (9), the target SIR determining unit 34 communicates the determinedtarget SIR for the received signal (=12 dB) to the base station 2, andat the same time, in (10), communicates it to the respective transportchannel target SIR updating units 36 and 361 to 36 n. Here, the targetSIRs for the respective transport channel are updated to the target SIRfor the received signal (=12 dB) communicated to the base station 2.

Hereinafter, with reference to FIG. 5, an operation in the base station2 according to this embodiment will be described. The base station 2 isconfigured to implement the operation below in predetermined time slots.

As shown in FIG. 5, in step S1001, the SIR measuring unit 26 measuresthe SIR of a received signal amplified at the amplifier unit 21 andsubjected to demodulation processing at the demodulator unit 25.

In step S1002, the pattern determining unit 24 compares the SIR measuredby the SIR measuring unit 26 with a target SIR for the received signalcommunicated from the target SIR determining unit 34 of the radiocontrol station 3.

Here, the pattern determining unit 24 keeps the latest target SIR untilit receives a new target SIR from the radio control station 3.

When the measured SIR exceeds the target SIR (or the measured SIR is notless than the target SIR), in step S1003, the pattern determining unit24 determines insertion of down information showing “transmit powerdown” in transmit power control bits.

On the other hand, when the measured SIR is below the target SIR (or themeasured SIR is not more than the target SIR), in step S1004, thepattern determining unit 24 determines insertion of up informationshowing “transmit power up” in transmit power control bits.

In step S1005, the frame generating unit 23 adds the transmit powercontrol bits determined by the pattern determining unit 24 to data bitsto be transmitted, thereby generating a transmission frame.

In step S1006, the modulator unit 22 performs modulation processing onthe transmission frame generated by the frame generating unit 23, andthe amplifier unit 21 amplifies the transmit power of the transmissionframe for transmission to the mobile station 1.

According to this embodiment, when the radio control station measuresthe channel quality of a control transport channel in a period shorterthan a predetermined period, and the channel quality of the controltransport channel is below a target channel quality, a target SIR for areceived signal is determined and communicated to the base station 2,breaking in the predetermined period. This can keep a load increase inthe radio control station to a minimum and also keep the circuitcapacity between the radio control station and the base station to aminimum, and an adequate circuit quality can be maintained.

Second Embodiment

With reference to FIGS. 6 to 8, a second embodiment of the presentinvention, mainly differences from the above-described first embodiment,will be described. FIG. 6 is a block diagram showing the configurationof a radio control station 3 according to this embodiment.

The radio control station 3 in this embodiment is configured to includea storage unit 37 a in addition to the components of the radio controlstation 3 in the above-described first embodiment. Here, the storageunit 37 a is configured to store a predetermined threshold for thechannel quality of a control transport channel.

A control transport channel quality monitoring unit 37 in thisembodiment includes a control transport channel quality measurementtimer, and is configured to monitor, within a time measured by thecontrol transport channel quality measurement timer, the channel quality(the number of CRC-NGs in this embodiment) of a control transportchannel measured at a control transport channel quality measuring unit35.

Here, the time measured by the control transport channel qualitymeasurement timer is set shorter than a time measured by a target SIRdetermination timer.

Also, the control transport channel quality monitoring unit 37 has thefunction of comparing the channel quality of a control transport channelwith the predetermined threshold.

Specifically, when the number of CRC-NGs received in the controltransport channel within the time measured by the control transportchannel quality measurement timer exceeds the predetermined threshold,the control transport channel quality monitoring unit 37 instructs thecontrol transport channel target SIR updating unit 36 to increase atarget SIR for the control transport channel, and also communicates thatfact to a target SIR communication control unit 38.

The target SIR communication control unit 38 is configured toimmediately instruct the control transport channel target SIR updatingunit 36 to communicate a current target SIR for the control transportchannel to a target SIR determining unit 34, according to an instructionfrom the control transport channel quality monitoring unit 37 even whena predetermined period has not come.

Also, the target SIR communication control unit 38 may be configured toalso immediately instruct the respective user transport channel targetSIR updating units 361 to 36 n to communicate current target SIRs forthe respective user transport channels to the target SIR determiningunit 34, according to an instruction from the control transport channelquality monitoring unit 37 even when the predetermined period has notcome.

Hereinafter, with reference to FIG. 7, an operation in the radio controlstation of this embodiment will be described.

As shown in FIG. 7, in step S201, the transport channel target SIRupdating units 36 and 361 to 36 n set initial target SIR values. Here,the initial target SIR values to be set are predetermined for thetransport channels by parameters.

Then, the operation divides into a loop for a control transport channel(S202 to S207) and a loop for user transport channels (S208 to S212).

In the loop for the user transport channels, in step S208, a timer unit38 a starts the target SIR determination timer for monitoring thepredetermined period.

In step S209, user transport channel quality measuring units 351 to 35 nmeasure the channel qualities of the respective user transport channels.

In step S210, the user transport channel target SIR updating units 361to 36 n compare the measured channel qualities of the respective usertransport channels with preset target channel qualities for therespective user transport channels, and update the target SIRs for therespective user transport channels.

In step S211, the target SIR communication control unit 38 determineswhether the time measured by the target SIR determination timer withinthe timer unit 38 a has expired or not, that is, whether thepredetermined period has come or not.

When the determination is yes (“Y” in step S211), the operation proceedsto step S212. When the determination is no (“N” in step S211), theoperation repeats the process of steps S209 to S211 by loop processing.

In step S212, the target SIR communication control unit 38 instructs therespective user transport channel target SIR updating units 361 to 36 nto immediately communicate current target SIRs for the respective usertransport channels to the target SIR determining unit 34. The target SIRdetermining unit 34 determines a target SIR for a received signal, basedon the communicated target SIRs for the respecitive user transportchannels, so that the channel qualities of all user transport channelssatisfy required channel qualities.

On the other hand, in the loop for the control transport channel, instep S202, the control transport channel quality monitoring unit 37starts the control transport quality measurement timer.

In step S203, the control transport channel quality measuring unit 35measures the channel quality (the number of CRC-NGs) of the controltransport channel.

In step S204, the control transport channel quality monitoring unit 37determines whether the time measured by the control transport qualitymeasurement timer has expired or not.

When the determination is yes (“Y” in step S204), the operation proceedsto step S205. When the determination is no (“N” in step S204), theoperation repeats the process of steps S203 to S204 by loop processing.

In step S205, the control transport channel quality monitoring unit 37determines whether the number of CRC-NGs measured by the controltransport channel quality measuring unit 35 exceeds the predeterminedthreshold (number of CRC-NGs) stored in the storage unit 37 a or not.

When the determination is yes (“Y” in step S205), the operation proceedsto step S206. On the other hand, when the determination is no (“N” instep S205), the control transport quality measurement timer is reset,and the operation returns to step S202.

In step S206, the control transport channel quality monitoring unit 37communicates the fact that the measured number of CRC-NGs exceeds thepredetermined threshold to the control transport channel target SIRupdating unit 36 and the target SIR communication control unit 38, andthe control transport channel target SIR updating unit 36 increases acontrol transport channel target SIR.

In step S207, the target SIR communication control unit 38 instructs therespective transport channel target SIR updating units 36 and 361 to 36n to immediately communicate current target SIRs for the respectivetransport channels to the target SIR determining unit 34. The target SIRdetermining unit 34 determines a target SIR for the received signal,based on the communicated target SIRs for the respective transportchannels, so that the channel qualities of all transport channelssatisfy required channel qualities.

In step S213, the target SIR determining unit 34 communicates thedetermined target SIR for the received signal to the base station 2, andalso communicates the target SIR for the received signal to therespective transport channel target SIR updating units 36 and 361 to 36n

In step S214, the transport channel target SIR updating units 36 and 361to 36 n update the respective transport channel target SIRs, based onthe communicated target SIR.

With reference to FIG. 8, an example of update transitions of targetSIRs for the respective transport channels in this embodiment under thesame conditions as in the example of FIG. 4 will be illustrated. In theexample of FIG. 8, the predetermined threshold is “2.”

In (1), initial target SIRs for all transport channels are set at 10 dB.

In (2), although the time measured by the control transport channelquality measurement timer has expired, since the number of CRC-NGsmeasured by the control transport channel quality measuring unit 35 doesnot exceed the predetermined threshold (“2”), nothing is done.

In (3), since the time measured by the target SIR determination timerhas expired, the target SIR determining unit 34 compares current targetSIRs for all transport channels, and determines a target SIR of thehighest quality as a target SIR for a received signal.

Here, since three CRC-OKs are reported on a user transport channel 1 (noCRC-NG is reported), the target SIR for the user transport channel 1 isreduced to 7 dB.

Also, since two CRC-OKs are reported on a user transport channel 2 (noCRC-NG is reported), the target SIR for the user transport channel 2 isreduced to 8 dB.

Accordingly, the target SIR determining unit 34 determines 8 dB, whichis the target SIR for the user transport channel 2, as a target SIR forthe received signal, and in (4), communicates the target SIR for thereceived signal (=8 dB) to the base station 2.

Also, in (5), the target SIR determining unit 34 communicates the targetSIR for the received signal (=8 dB) to the respective transport channeltarget SIR updating units 36 and 361 to 36 n. The respective transportchannel target SIR updating units 36 and 361 to 36 n update the targetSIRs for the respective transport channel to the communicated target SIRfor the received signal (=8 dB).

At this time, although the time measured by the control transportchannel quality measurement timer has not expired yet, the controltransport channel quality measurement timer is reset.

In (6), suppose that the time measured by the control transport channelquality measurement timer has expired, and the number of CRC-NGsmeasured by the control transport channel quality measuring unit 35exceeds the predetermined threshold (“2”).

Here, the target SIR determining unit 34 determines 9 dB, which is thetarget SIR for the control transport channel, as a target SIR for thereceived signal, so as to satisfy the channel qualities of all transportchannels, and in (7), communicates the target SIR for the receivedsignal (=9 dB) to the base station 2.

When it is determined that the number of CRC-NGs measured by the controltransport channel quality measuring unit 35 exceeds the predeterminedthreshold (“2”), the target SIR for the control transport channel isincreased from 8 dB to 9 dB.

Also, in (8), the target SIR determining unit 34 communicates the targetSIR for the received signal (=9 dB) to the respective user transportchannel target SIR updating units 361 to 36 n. The respective usertransport channel target SIR updating units 361 to 36 n update thetarget SIRs for the respective user transport channels to thecommunicated target SIR for the received signal (=9 dB).

At this time, although the time measured by the target SIR determinationtimer has not expired yet, the target SIR determination timer is reset.

In (9), although the time measured by the control transport channelquality measurement timer has expired, since the number of CRC-NGsmeasured by the control transport channel quality measuring unit 35 doesnot exceed the predetermined threshold (“2”), nothing is done.

In (10), since the time measured by the target SIR determination timerhas expired, the target SIR determining unit 34 compares current targetSIRs for all transport channels, and determines a target SIR of thehighest quality as a target SIR for the received signal.

Here, since two CRC-OKs and one CRC-NG are reported on the usertransport channel 1, the target SIR for the user transport cannel 1 isreduced to 8 dB.

Also, since three CRC-OKs are reported (no CRC-NG is reported) on theuser transport channel 2, the target SIR for the user transport cannel 2is reduced to 6 dB.

Accordingly, the target SIR determining unit 34 determines 8 dB, whichis the target SIR for the user transport channel 1, as a target SIR forthe received signal, and in (11), communicates the target SIR for thereceived signal (=8 dB) to the base station 2.

Also, in (12), the target SIR determining unit 34 communicates thetarget SIR for the received signal (=8 dB) to the respective transportchannel target SIR updating units 36 and 361 to 36 n. The respectivetransport channel target SIR updating units 36 and 361 to 36 n updatethe target SIRs for the respective transport channel to the communicatedtarget SIR for the received signal (=8 dB).

At this time, although the time measured by the control transportchannel quality measurement timer has not expired yet, the controltransport channel quality measurement timer is reset.

According to this embodiment, when a measured number of CRC-NGs exceedsa predetermined threshold, the control transport channel target SIRupdating unit 36 increases a target SIR for the control transportchannel, and a target SIR for the received signal updated based on thetarget SIR for the control transport channel is immediately communicatedto the base station. Therefore, even when the amount of control dataflowing in the control transport channel is small, deterioration in thechannel quality of the control transport channel can be coped with inreal time.

Although the present invention has been described in detail using theembodiments above, it is obvious for those skilled in the art that thepresent invention is not limited to the embodiments described in thepresent application. The devices in the present invention can beimplemented as modified and altered embodiments without departing fromthe spirit and scope of the present invention as defined by thedescription of the claims. Accordingly, the description in the presentapplication is for illustrative purposes, and is not meant to limit thepresent invention.

INDUSTRIAL APPLICABILITY

According to the present invention, a controller equipment and a radiocommunication method can be provided with which, in the case where aradio control station communicates a target SIR in outer loop transmitpower control to a base station in predetermined periods, not in realtime, an adequate circuit quality can be maintained with a minimumincrease in the load of the radio control station and a minimum increasein the circuit capacity between the radio control station and the basestation.

1. A controller equipment comprising: a measuring unit configured tomeasure channel qualities of a control channel and a user channelseparated from a received signal; an updating unit configured to updatetarget circuit qualities for the control channel and the user channel,based on results of measurement of the channel qualities by themeasuring units; a communicating unit configured to communicate, in apredetermined period, the updated target circuit qualities for thecontrol channel and the user channel; and a target circuit qualitydetermining unit configured to determine a target circuit quality forthe received signal, based on the target circuit qualities for thecontrol channel and the user channel communicated from the communicatingunit, so that all of the control channel and the user channel satisfy arequired channel quality; wherein, when the channel quality of thecontrol channel satisfies a predetermined condition, the communicatingunit is configured to communicate at least the target circuit qualityfor the control channel to the target circuit quality determining unit;and the target circuit quality determining unit is configured todetermine the target circuit quality for the received signal, based onthe communicated target circuit quality for the control channel.
 2. Thecontroller equipment as set forth in claim 1, wherein the communicatingunit is configured to compare the channel quality of the control channelwith a predetermined threshold in a period shorter than thepredetermined period, and to communicate the updated target circuitquality for the control channel to the target circuit qualitydetermining unit based on a result of the comparison.
 3. The controllerequipment as set forth in claim 1, wherein: when the channel quality ofthe control channel satisfies a predetermined condition, thecommunicating unit is configured to communicate the target circuitqualities for the control channel and the user channel to the targetcircuit quality determining unit; and the target circuit qualitydetermining unit is configured to determine the target circuit qualityfor the received signal, based on the communicated target circuitqualities for the control channel and the user channel.